The World Wide Web of the Internet is the most successful distributed application in the history of computing. In the Web environment, client machines effect transactions to Web servers using the Hypertext Transfer Protocol (HTTP), which is a known application protocol providing users access to files (e.g., text, graphics, images, sound, video, etc.). A standard page description language known as HyperText Markup Language (HTML) provides basic document formatting and allows the developer to specify “links” to other web servers and files and also to specify pointers to other files located on a Web server which are to be downloaded by the client and displayed as embedded elements of the web page. Examples of such embedded elements include files containing images for display, and in particular files containing the images for display as “action buttons”. In the Internet paradigm, a network path to a file or web server is identified by a so-called Uniform Resource Locator (URL) having a special syntax for defining a network connection. Use of an HTML-compatible browser (for example, Netscape Navigator) at a client machine involves specification by a user of a link via the URL (Netscape Navigator is a trademark of Netscape Communications Corporation). In response, the client makes a request to the web server identified in the link and receives in return a document formatted according to HTML.
There are more and more frequent examples of Internet web pages that have the look and feel of a first company, such as International Business Machines Corporation (IBM), including use of that company's banner headings and left hand side titles, but which do not in fact originate from that first company. The main content of the web page originates from a second, unrelated company trying to pass itself off as the first company. For example, there are a number of web pages that have the look and feel of the IBM web pages, including the use of the IBM logo and IBM banner heading. These web pages have a structure that has an Action URL that points to a web page belonging to and controlled by the second company, but the Action URL itself contains tags such as SRC tags that point to elements of web pages belonging to the first company. For example, a web page that has no association with IBM includes SRC tags that point to two image files http://www.ibm.com/klingon/logo_sp.gif and to http://www.ibm.com/klingon/i_support.gif, which are both located on Web servers belonging to IBM. That web page, when rendered in a browser, then includes the IBM logo and a “Support” action button identical to that on IBM pages, even to the extent of being updated if the IBM one changes. By the use of SRC tags, the second company is including material from the first company's Web site by reference without actually having that material included in the source text of the second company's web page.
While on the one hand it can be argued that this constitutes a form of copyright infringement, it can be seen that this practice presents a more worrying possibility for fraud, as it is entirely possible for actions associated with the images to operate in a manner completely contrary to the business objectives of the image owner.
So it would be desirable to provide a method of checking that an element of a web page is being downloaded for use in web pages originating from the same web server as the web server where the element is being stored.